How to Recognize Threads? A Guide by Beata Dąbrowska
Online Store POLBERIS
www.sklep.polberis.pl Email: biuro@polberis.pl Phone: 632614202
Thin Stainless Steel Fittings: External BSPT thread, internal BSPP thread, generally referred to as BSP.
Exceptions: NPT threads can occasionally be found here, but they are very rare in Poland, and these fittings have thicker walls and are non-standard.
- Stainless Steel Nipple 316
- Stainless Steel Elbow 316
- Stainless Steel Tee DN20
Cast Iron, Galvanized, and Black Fittings: External BSPT thread, internal BSPP thread, generally referred to as BSP.
- Galvanized Cast Iron Elbow
- Galvanized Cast Iron Angle Fitting
- Galvanized Cast Iron End Cap
Exceptions: NPT threads can be found here, but they are extremely rare in Europe, and these fittings have very thick walls and are non-standard.
Metric threads do not occur here.
Steel Threaded Flanges Manufactured to EN Standards – BSP thread.
- BSP Threaded Flange
American Steel Threaded Flanges Manufactured to ANSI Standards – NPT thread.
- NPT Threaded Flange 316L
Valves: Threaded in inches, such as ½’’, ¾’’, 1’’, etc., most often BSP thread.
- Brass Nipple Valve
- Water Valve with Handle
Exceptions: NPT thread – If the valve has an NPT thread, it is usually written on it.
- High-Pressure NPT Valve
Metric Threads: Rarely found in valves, it’s unlikely to encounter them.
High-Pressure Fittings According to American ASME B16.11 Standards – NPT thread.
Pressure class 2000, 3000, or 6000.
- NPT Stainless Steel Elbow Class 3000 316L
- NPT Stainless Steel Reducing Union A105 206 bar 3000 lbs
- High-Pressure NPT Tee
Exception: BSP thread – If the American fitting has BSP, BSPT, or BSPP threads, it will be marked (labeled).
Fittings with Protruding Ends – Typically have UN or UNF threads.
- Steel JIC UNF Elbow for Hydraulic Systems
- Galvanized Steel JIC Nipple
Metric Thread: Common in hydraulic systems, it’s finer to the eye compared to inch threads. If you’re not dealing with hydraulic systems, you’re unlikely to encounter metric threads.
Metric threads are not found in cast iron or American-standard fittings.
- M24X1.5 Nipple
Black Steel Fittings, Thin – Only BSP thread.
- Black Steel Union
- Large Steel Union for Welding
Hose Fittings: Can have metric, inch, or NPT threads. You will need to measure them according to the table provided on our website.
How to Measure BSP, BSPT, NPT, UNF, JIC, Metric Threads
- Brass DN10 Hose Fitting
- NPT Steel Hose Nipple
Screw Fittings for Tubing: These fittings have inch BSP or NPT threads. You need to measure them according to the provided table.
How to Measure BSP, BSPT, NPT, UNF, JIC, Metric Threads
- Screw Fitting for Tubing
- Nipple for Tubing
Branch Fittings (Threadolets): These have NPT threads.
- NPT Threadolet A105
Exception: A BSP-threaded threadolet is possible, but this is rare and can only be found at PolBeris. It is made exclusively on our request.
Still confused? Call us at 632614202 or email us at biuro@polberis.pl. We will help you for free. Feel free to contact us!
American NPT Threads are made according to ANSI B1.20.1 standards.
BSP Thread – BSPP (British Standard) follows Whitworth standards, also known as cylindrical, straight pipe, ISO 228 Rp, ISO 7-1 Rp. It is not tapered.
BSPT Thread – Tapered, also known as Rc.